1. Field of the Invention
This invention relates to medical equipment, and more particularly to disposable hypodermic needles.
2. Description of the Prior Art
International law applicable to construction-specification of disposable hypodermic syringes does not exist to mandate construction criteria for an absolute on-use limitation. Syringe/needle-sharing among drug-users is fueling ravishing disease-spread. Accidental-sticks to World Health Care personnel have spread infection alarmingly. It has been a long-existing goal of syringe designers to create a disposable syringe which will minimize exposure of an infected needle and help prevent transmittal of often fatal diseases.
A tubular serum reservoir is traditionally made of extruded polymeric plastic. It is closed at lower end by a bulkhead, which has an opening to allow serum infusion/discharge. Totally open at the grippable upper-end, it receives a sliding, fluid-tight plunger, which forces medicine out through a needle and which creates internal vacuum when moved outwardly.
Some of the known devices provide for the use of sheaths, or sleeves which enclose the needle, or a needle tip during non-use. Some of the devices suggest the use of collapsible sleeves to permit injection. Still others teach the use of self-destructing syringes. However, none of the known devices provides for the use of a disposable syringe having means for disinfecting an injection site during the process of injection, with the piston being designed to collapse and prevent re-use of the syringe. Additionally, many known devices are complicated to manufacture, often inconvenient and unreliable in use and do not afford total sterility of the needle.